Stereodivergent Synthesis of Iminosugars from Stannylated Derivatives of (S)-Vinylglycinol

A versatile stereocontrolled synthesis of 2-deoxyiminosugar C-glycosides and their evaluation as glycosidase inhibitors

A highly enantioselective synthesis of (R,S) or (S,S)-2,6-disubstituted dehydropiperidines has been previously achieved through Sn/Li transmetalation of the corresponding stannylated dehydropiperidines or of their precursors. Herein, we successively consider their Upjohn's syn dihydroxylation and their anti-dihydroxylation via an epoxidation reaction followed by epoxide opening reaction. The stereochemical course of these reactions was first reported including the use of appropriate protecting groups before considering the conversion of the obtained compounds into NH or NMe iminosugar hydrochlorides. A primary evaluation of the designed iminosugar C-glycosides as glycosidase inhibitors suggests candidates for the selective inhibition of α-galactosidase, amyloglycosidase and naringinase. Beyond the reported results, the method constitutes a highly modulable route for the synthesis of well stereodefined iminosugar C-glycosides, an advantage which might be used for the design of iminosugars to enhance their biological properties.

[1,4]-sigmatropic rearrangement of chiral nitrones and their utilization in the synthesis of new iminosugars

A new mechanism of nitrone epimerization via [1,4]-sigmatropic rearrangement was proposed and a set of epimeric iminosugars was synthesized.

Divergent synthesis of various iminocyclitols from d-ribose

A very efficient route to the diastereoselective synthesis of polyhydroxy pyrrolidines, piperidines and azepanes from an aldehyde derivative of ribose is reported.